1. Field of the Invention
The present invention relates generally to internal combustion engine service and repair equipment and, more particularly, to an engine valve compressing machine which allows for the quick and easy removal of valve springs from engine cylinder heads.
2. Description of the Related Art
In the art of engine service and repair equipment of to internal combustion engines, a wide variety of methods are currently utilized in order to assist a mechanic in the removal and replacement of engine valves and valve springs. Due to the tremendous urging forces provided by the valve lifter springs, removing these valves can require far more force than can be generated by the unaided hand. As a result, hand held air clamps and manual screw clamps are used in a widespread manner to accomplish this task.
In the related art, other methods of providing a pneumatic assistance device for this task are known. A search of the prior art did not disclose any patents that read directly on the claims of the instant invention; however, the following references were considered related:
U.S. Pat. No. 1,034,874, issued in the name of Clark, discloses a device for removing automotive valve springs wherein a lever arm is used to compress the valve spring in order to remove it. The device includes a hook support attached to the lever via a chain that, when placed against the valve head, places the fulcrum of the lever arm upon the valve head, allowing the spring to be compressed without actuating the valve.
U.S. Pat. No. 2,586,050, issued in the name of Jensen, and U.S. Pat. No. 3,295,193, issued in the name of Maness, disclose a devices for removing automotive valve springs wherein a pry bar-like lever arm is used to compress the springs for removal either from the stem-side or from the headside of the valve assembly. These devices place the fulcrum of the lever arm upon the cylinder head or other structural member of the automobile engine.
The inventions disclosed in the '874, '050, and '193 all suffer from drawbacks that distinguish them from the present invention and illustrate the novel and advantageous features of the present invention. First, these devices are designed to manually compress a single valve spring, requiring the user to repeatedly perform the operation on a multitude of valves, spending a great deal of time. Second, these devices are all manually operated, requiring the user to exert his own energy in compressing the valve springs for their removal and can amount to an extraordinarily large task when repeated on a multitude of valve springs. Finally, the fact that these lever-arm type devices place the fulcrum directly on the engine structure creates the risk of damaging engine parts during their use.
U.S. Pat. No. 5,375,308, issued in the name of Harris, discloses a device for removing automotive valve springs wherein a pneumatic compression device, powered by a compressed air source, is used to compress the valve spring so that it can be removed. Although this device relieves the user of the burden of having to manually compress the spring and limits the possibility of damaging the engine structure with a lever-arm type device, this device can only be used on one spring at a time, requiring repeated use. It also requires the use of large, expensive compressor units and forces the user to manage a bulky hose.
U.S. Pat. No. 5,371,932, issued in the name of Bryan et al., discloses a device for removing automotive valve springs wherein an engine cylinder head is placed upon the table portion of the device and secured thereto. A compression plate, connected to a hydraulic actuator is mounted above the table and, when activated, fits over the entire row valve springs, compressing all of them at the same time and allowing for their removal. The table portion rotates along an axis parallel to the length of the cylinder head so as to allow for use with varying valve angles. This invention, however, is inadequate due to the fact that it will accommodate only cylinder heads that contain valves in a single row and of a limited size. Many modern engine designs incorporate the use of multiple valves per single cylinder, thus resulting in a non linear arrangement that this device will not accommodate.
Finally, U.S. Pat. No. 4,513,486, issued in the name of Raczek, discloses a valve retainer for automotive valve repair wherein the device is secured within the engine cylinder by screwing it into the spark plug threads. Once inserted, the device can be actuated so that a lever arm rests upon the valve head, preventing it from opening and thus allowing the valve spring to be compressed without opening the valve. This device, however, does not include any means for compressing or removing the valve spring, and thus does not address the purpose of the present invention as it does not perform a like function.
While some features are incorporated into this invention in combination, other elements are different enough as to make the combination distinguished over the related art. Consequently, a need has therefore been felt for an engine valve compressing machine which allows for the quick and easy compression and removal of valve springs from engine cylinder heads.